C++ PCOL::IsSpecial方法代码示例

char *TDBWMI::MakeWQL(PGLOBAL g)
  {
  char  *colist, *wql/*, *pw = NULL*/;
  int    len, ncol = 0;
  bool   first = true, noloc = false;
  PCOL   colp;

  // Normal WQL statement to retrieve results
  for (colp = Columns; colp; colp = colp->GetNext())
    if (!colp->IsSpecial() && (colp->GetColUse(U_P | U_J_EXT) || noloc))
      ncol++;

  if (ncol) {
    colist = (char*)PlugSubAlloc(g, NULL, (NAM_LEN + 4) * ncol);

    for (colp = Columns; colp; colp = colp->GetNext())
      if (!colp->IsSpecial()) {
        if (colp->GetResultType() == TYPE_DATE)
          ((DTVAL*)colp->GetValue())->SetFormat(g, "YYYYMMDDhhmmss", 19);

        if (colp->GetColUse(U_P | U_J_EXT) || noloc) {
          if (first) {
            strcpy(colist, colp->GetName());
            first = false;
          } else
            strcat(strcat(colist, ", "), colp->GetName());
      
          } // endif ColUse

        } // endif Special

  } else {
    // ncol == 0 can occur for queries such that sql count(*) from...
    // for which we will count the rows from sql * from...
    colist = (char*)PlugSubAlloc(g, NULL, 2);
    strcpy(colist, "*");
  } // endif ncol

  // Below 14 is length of 'select ' + length of ' from ' + 1
  len = (strlen(colist) + strlen(Wclass) + 14);
  len += (To_CondFil ? strlen(To_CondFil->Body) + 7 : 0);
  wql = (char*)PlugSubAlloc(g, NULL, len);
  strcat(strcat(strcpy(wql, "SELECT "), colist), " FROM ");
  strcat(wql, Wclass);

  if (To_CondFil)
    strcat(strcat(wql, " WHERE "), To_CondFil->Body);

  return wql;
  } // end of MakeWQL

bool TDBTBL::InitTableList(PGLOBAL g)
  {
  int     n;
  uint    sln;
  char   *scs;
  PTABLE  tp, tabp;
  PCOL    colp;
  PTBLDEF tdp = (PTBLDEF)To_Def;
  PCATLG  cat = To_Def->GetCat();
  PHC     hc = ((MYCAT*)cat)->GetHandler();

  scs = hc->get_table()->s->connect_string.str;
  sln = hc->get_table()->s->connect_string.length;
//  PlugSetPath(filename, Tdbp->GetFile(g), Tdbp->GetPath());

  for (n = 0, tp = tdp->Tablep; tp; tp = tp->GetNext()) {
    if (TestFil(g, To_CondFil, tp)) {
      tabp = new(g) XTAB(tp);

      if (tabp->GetSrc()) {
        // Table list is a list of connections
        hc->get_table()->s->connect_string.str = (char*)tabp->GetName();
        hc->get_table()->s->connect_string.length = strlen(tabp->GetName());
        } // endif Src

      // Get the table description block of this table
      if (!(Tdbp = GetSubTable(g, tabp))) {
        if (++Nbc > Maxerr)
          return TRUE;               // Error return
        else
          continue;                  // Skip this table

      } else
        RemoveNext(tabp);            // To avoid looping

      // We must allocate subtable columns before GetMaxSize is called
      // because some (PLG, ODBC?) need to have their columns attached.
      // Real initialization will be done later.
      for (colp = Columns; colp; colp = colp->GetNext())
        if (!colp->IsSpecial())
          if (((PPRXCOL)colp)->Init(g, NULL) && !Accept)
            return TRUE;

      if (Tablist)
        Tablist->Link(tabp);
      else
        Tablist = tabp;

      n++;
      } // endif filp

    } // endfor tp

  hc->get_table()->s->connect_string.str = scs;
  hc->get_table()->s->connect_string.length = sln;

//NumTables = n;
  To_CondFil = NULL;        // To avoid doing it several times
  return FALSE;
  } // end of InitTableList

PCOL TDBASE::InsertSpecialColumn(PCOL colp)
  {
  if (!colp->IsSpecial())
    return NULL;

  colp->SetNext(Columns);
  Columns = colp;
  return colp;
  } // end of InsertSpecialColumn

PCOL TDBTBL::InsertSpecialColumn(PCOL scp)
  {
  PCOL colp;

  if (!scp->IsSpecial())
    return NULL;

  if (scp->GetAmType() == TYPE_AM_TABID)
    // This special column is handled locally
    colp = new((TIDBLK*)scp) TBTBLK(scp->GetValue());
  else  // Other special columns are treated normally
    colp = scp;

  colp->SetNext(Columns);
  Columns = colp;
  return colp;
  } // end of InsertSpecialColumn

bool TDBXCL::OpenDB(PGLOBAL g)
  {
  if (Use == USE_OPEN) {
    /*******************************************************************/
    /*  Table already open, just replace it at its beginning.          */
    /*******************************************************************/
		M = N = 0;
		RowFlag = 0;
    New = TRUE;
		return Tdbp->OpenDB(g);
    } // endif use

  if (Mode != MODE_READ) {
    /*******************************************************************/
    /* Currently XCOL tables cannot be modified.                       */
    /*******************************************************************/
    strcpy(g->Message, "XCOL tables are read only");
    return TRUE;
    } // endif Mode

  if (InitTable(g))
    return TRUE;
  
  /*********************************************************************/
  /*  Check and initialize the subtable columns.                       */
  /*********************************************************************/
  for (PCOL cp = Columns; cp; cp = cp->GetNext())
    if (!cp->IsSpecial())
      if (((PPRXCOL)cp)->Init(g, NULL))
        return TRUE;

  /*********************************************************************/
  /*  Physically open the object table.                                */
  /*********************************************************************/
	if (Tdbp->OpenDB(g))
		return TRUE;

  Use = USE_OPEN;
	return FALSE;
  } // end of OpenDB